The electronics industry has experienced an ever increasing demand for smaller and faster electronic devices which are simultaneously able to support a greater number of increasingly complex and sophisticated functions. Accordingly, there is a continuing trend in the semiconductor industry to manufacture low-cost, high-performance, and low-power integrated circuits (ICs). Thus far these goals have been achieved in large part by scaling down semiconductor IC dimensions (e.g., minimum feature size) and thereby improving production efficiency and lowering associated costs. However, such scaling has also introduced increased complexity to the semiconductor manufacturing process. Thus, the realization of continued advances in semiconductor ICs and devices calls for similar advances in semiconductor manufacturing processes and technology.
Graphene, a two-dimensional (2-D) sheet of carbon atoms bonded to one another in a hexagonal crystal lattice, has recently been introduced as a potential replacement channel material for transistor devices. In addition to its high intrinsic mobility, graphene has attracted great interest for its other unique properties such as large current densities, thermodynamic and mechanical stability, and high saturation velocity, among others. Graphene films have often been obtained by mechanical exfoliation (e.g., from a bulk graphite source), but mechanical exfoliation results in graphene films that are small (e.g., tens of microns) and non-scalable. Large-area graphene films have been produced by methods such as epitaxial growth on silicon carbide (SiC) substrates and chemical vapor deposition (CVD)-growth (e.g., involving the catalyzed decomposition of hydrocarbons on a metal surface), but such methods also have drawbacks (e.g., high-cost of SiC substrates and high processing temperature for SiC epitaxial growth). Regardless of the technique used for producing graphene films, the fabrication of graphene-based devices generally involves transfer of a graphene layer (e.g., from a growth substrate or from the bulk graphite source), and onto a target substrate upon which the graphene-based device will be fabricated. As a result of the transfer process, grain boundaries, point defects, wrinkles, folds, tears, cracks, impurities, or other defects may be introduced into the transferred graphene layer and thereby detrimentally affect the properties of any subsequently fabricated devices. Thus, existing techniques have not proved entirely satisfactory in all respects.